Remember, You Can Trial iOS 9
If you're already on iOS 8.4.1, you can trial the iOS 9 update. What we mean is that you should be able to install the iOS 9 update and downgrade back to iOS 8.4.1 (for a short period of time) if you decide that you don't like its features and performance.
Apple typically signs off on old updates for one to two weeks before it stops. During that period, you're able to downgrade to the last version of iOS software. In this case, iOS 8.4.1. This gives you an out if you decide that iOS 9 is too much trouble.
If you're already familiar with the downgrade process, there's incentive to download iOS 9 right away. If you're not, get familiar with it right now.
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